The present invention relates generally to chucks for use with drills or electric or pneumatic power drivers. More particularly, the present invention relates to a chuck of the keyless type which may be tightened or loosened by hand.
Both hand and electric or pneumatic tool drivers are well known. Although twist drills are the most common tools used with such drivers, the tools may also comprise screw drivers, nut drivers, burrs, mounted grinding stones, and other cutting or abrading tools. Since the tools may have shanks of varying diameter or may have a polygonal cross-section, the device is usually provided with a chuck that is adjustable over a relatively wide range. The chuck may be attached to a driver by a threaded or tapered bore and may be formed integrally with the drive shaft of the drill.
A wide variety of chucks have been developed in the art. In one form of chuck, three jaws spaced circumferentially approximately 120 degrees apart from each other are constrained by angularly disposed passageways in a body attached to the drive shaft. The chuck is configured so that rotation of the body in one direction with respect to a constrained nut forces the jaws toward or away from a gripping relationship with a tool shank. Such a chuck may be keyless if it can be tightened or loosened by manual rotation.
In another form of chuck, a nut is axially movably disposed about the chuck body so that axial movement of the nut with respect to the chuck body moves the chuck jaws within passageways in the chuck body. The nut defines threads on an outer circumferential surface that mate with threads defined on an inner circumferential surface of a sleeve. Rotation of the sleeve with respect to the chuck body moves the nut axially to drive the jaws within the passageways to grip and ungrip a tool.
Various configurations of keyless chucks are known in the art and are desirable for a variety of applications.
The present invention recognizes and addresses the foregoing considerations, and others, of prior art construction and methods. Accordingly, it is an object of the present invention to provide an improved chuck for use with a manual or powered driver.
This and other objects are achieved by a chuck for use with a manual or powered driver having a rotatable drive shaft. The chuck includes a generally cylindrical body having a nose section and a tail section. The tail section is adapted to rotate with the drive shaft, and the nose section has an axial bore formed therein. A driver is axially movably disposed about the body. A generally cylindrical sleeve is rotatably mounted about the body. A grip is mounted in the body in communication with the axial bore and in operative communication with the driver. The driver is in communication with the sleeve and the body so that, in a first state of the chuck, rotation of the sleeve with respect to the body in a closing direction moves the grip toward the axis of the axial bore, and so that in a second state of the chuck, the sleeve does not rotate with respect to the body and the driver is axially reciprocal with respect to the sleeve and the body.
The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate one or more embodiments of the invention and, together with the description, serve to explain the principles of the invention.